Physics Excel Practice Lab

Purpose: To establish good techniques in graphing and interpretation of graphs using errors, trend lines, slope calculations, interpolating data.

Apparatus: Data table, computer with Excel

Procedure: 1) Plot the following data in Excel as follows;

a) Open Excelb) In column

A, right click and format cells to Number: 2 decimals

(as our data has a maximum of 2 decimals).This is your “x” data (if you like, insert a title into box 1 like displacement (m))

c) Do the same thing for column B (no difference for any version of Excel)

d) Insert data values with the “x” values in column A and the “y” values in column B. See above Screen Shot.

e) Highlight Column A and B from Cell A1 (or Cell A2 if you have a title like the Screen Shot below) and:

Time (s) Displacement (m)0 0

1.00 9.002.00 36.003.00 81.004.00 144.005.00 225.006.00 324.007.00 441.00

i) XP Excel and earlier: (Office 2007 skip to page 7) click on the Chart Wizard icon at the top or click on Insert tab and click on Chart.

Choose the XY (Scatter)and click Next>

Now, you can see this box open: it shows you a quick graph of how your final graph will look. Check that the y-axis data is on the vertical part of the graph and click Next>

Now we have an opportunity to “Taylor” up our graphs:Type in the titles for the chart (in the expected “y” vs.“x” format) so for this example, type in displacement versus time. The Value (X) is time (s) and Value (Y) is displacement (m).

Next, Click on the Gridlines tab.

Click on the Major gridlines for both axes (horizontal is done already). Click the Legend Tab.

Click off the Show Legend box as this wastes space and enlarges the graph.

Now click the Next> button. Save as a New Sheet. (Gives you a full page graph). Click Finish.

You should see a full page graph appear.

You can change the style of the dots (make them into circles for example to represent plotting error (3U Physics) or add error bars (4U Physics-input as percentages or input fixed ± values)!!) Click on the dots so they all appear yellow, and right click with your mouse. Click

Format Data Series.

Now you can play with the dots. Change the style to non-coloured circles of larger size. (Change the Background to white and change the size and Style).

Now your graph has points with error circles.

Click on the dots so they are all highlighted, and right click with your mouse. Click on Add Trendline.

Click on the Polynomial box and leave as Order: 2 to plot a best-fit curve.

Your new graph appears with a curve. Right click on the graph and Format Trendline.A new window appears and you can play with the Patterns (add colours, etc).

Click on the Options Tab and click the box Display Equation on Chart. (This is better used for linear graphs to give you slope). Click OK.

Right clicking in the graph area (not on a point) gives several options to Format Plot Area (colours, etc),

Chart Type (changes graph to another type of graph: not likely used), Source Data (allows you to manipulate Data Table (swap x for y if there was a mix-up), Chart Options (gives you the menu box with the original choices to label graphs, etc), and Location (save as New sheet if you didn’t do it earlier, for example)

ii) Office 2007: Click on the Insert Tab and click on Scatter and click on the first box (no lines).

f) The graph pops in the middle as a small page, and the Design Tab automatically opens. Click on Move Chart and save as a New Sheet

g) You should see your dots line up as a power curve. Click on the Layout Tab. Select Chart Title, Axis Titles, Legend (delete legend to expand graph space), Axes (default is fine) and Gridlines (Major is all that is needed as more lines crowd the graph and wastes ink!) and adjust as you wish.

h) Click on Trendline and choose More Trendline Options and pick Polynomial (of degree 2).

i) You now have a best-fit power curve through the points. Click on Design and choose a chart style showing larger points. (Scroll down to get selection).

j) Grade 11: We can add “circles” around the data points to see the data and to represent error. Click on the dots themselves so all the dots are selected at once. The Format tab opens with options. Click on Shape Fill and choose no fill to make them clear circled points.

k) Grade 12: You can also click on the Error Bar tab (in Layout) to include errors as a percentage or standard values. (Time would be 0.005s and displacement would be 0.005 m: half the smallest division) More Error Bar Options and choose error as 0.005 and Close. (These errors are quite small).